Anterior Cruciate Ligament Graft Research Articles

Survivorship and Outcomes of Meniscal Ramp Lesions Repaired Through a Posteromedial Portal During Anterior Cruciate Ligament Reconstruction: Outcome Study With a Minimum 10-Year Follow-up.

Several studies have demonstrated suture repair of ramp lesions of the medial meniscus via a posteromedial approach was associated with a significantly lower rate of secondary meniscectomy. However, these studies are not long-term and highlight the need for extended follow-up research to better understand the outcomes over a more extended period. To evaluate the long-term results and reoperation rate for the failure of arthroscopic all-inside suture repair of ramp lesions of the medial meniscus via a posteromedial approach during anterior cruciate ligament (ACL) reconstruction. Case series; Level of evidence, 4. All patients who underwent all-inside suture repair of the posterior segment of the medial meniscus (ramp lesion) via a posteromedial approach during ACL reconstruction at a minimum follow-up of 10 years were included in the study. Side-to-side anterior laxity was assessed preoperatively and postoperatively. Pre- and postoperative functional assessment was based on the subjective International Knee Documentation Committee score for activities of daily living and the Tegner activity scale for sporting ability. Reinterventions for meniscal repair failure and other complications were also recorded at the last follow-up. A total of 81 patients met the inclusion criteria for this study. Two patients had an ACL graft rupture with a new ramp lesion and were excluded from the analysis. Additionally, 15 patients were lost to follow-up, leaving a total of 64 patients in the final analysis. The mean follow-up was 124.8 months (range, 122.4-128.4 months). Mean side-to-side difference in anterior laxity significantly improved from 7.4 ± 1.5 mm (range, 5-12 mm) to 0.4 ± 1.3 mm (range, -3 to 4 mm) (P = .01). The mean subjective International Knee Documentation Committee score increased from 64.3 ± 13.4 (range, 34-92) before the operation to 91.1 ± 10.1 (range, 49-100) at the last follow-up (P = .001). The Tegner activity scale score at the last follow-up (6.3 ± 1.6) was lower than that before the trauma (7.1 ± 1.6) (P = .02). Fourteen patients (21.9%) had a failed meniscal repair and were reoperated. The mean time from initial repair to reoperation was 64.5 months (range, 13-126 months), and the median was 60.6 months. The multivariate analysis, including parameters such as lateral tenodesis (hazard ratio [HR], 1.62; P = .50), preoperative Tegner score (HR, 1.66; P = .41), preoperative laxity (HR, 1.75; P = .35), age at surgery (HR, 1.02; P = .97), and number of sutures (HR, 2.38; P = .19), did not reveal any factors associated with suture failure. The results show that arthroscopic repair of ramp lesions of the medial meniscus during ACL reconstruction using a posteromedial approach has a high failure rate at the 10-year follow-up, with half of these suture failures occurring within 5 years after the initial repair.

Evaluation of Return to Military Activities after Combining Anterior Cruciate Ligament Reconstruction with Modified Lateral Extra-articular Tenodesis Versus Anterior Cruciate Ligament Reconstruction Alone in Primary Anterior Cruciate Ligament Tear in Soldiers. A Randomized Comparative Study

Abstract Background: This study aimed to assess the clinical result, complications, failure rate, and return to resuming military duty of a single-stage anterior cruciate ligament reconstruction (ACLR) procedure utilizing quadrupled semitendinosus tendon graft joint with modified lateral extra-articular tenodesis (LET). This study evaluates the potential impact of combined modified LET with ACLR versus ACLR alone on the rate of return to high-impact military activities, which we call return to sports (RTSs), and the subsequent rate of the anterior cruciate ligament (ACL) graft failure. Materials and Methods: A total of 198 soldiers with primary ACL tears with a high-grade pivot test (grade 3) were included and randomized using the simple randomized method and divided into two groups. A consecutive cohort of military personnel with an isolated ACL tear undergoing ACLR with modified LET (group A, n = 116) and ACLR alone (group B, n = 82) were analyzed between 2016 and 2021. Both groups were followed up for a minimum of 2 years. Soldiers underwent a survey evaluating knee function (knee injury and osteoarthritis outcome score [KOOS]), RTS criteria (RTS type), symptoms (International Knee Documentation Committee [IKDC] subjective), activity level (Tegner score), and fear of movement (Tampa Scale of Kinesiophobia-11) to assess psychological readiness for sport participation. Results: Among these, a mean age of 32 ± 2.93 years underwent primary ACLR with modified LET (n = 116) or without LET (n = 82) procedure. A total of 31 soldiers (15.6%) experienced ACL graft failure, including 26 (31.7%) reconstructions without LET and 5 (4.3%) with LET. Combined with LET during primary ACLR, it lowered the risk of graft failure by 2.8 times. Multivariable analysis revealed a significant reduction in graft rupture risk (relative risk = 0.325, P = 0.029) associated with LET compared to ACLR alone after adjusting for age, anthropometric factors, and tibial slopes. 105 out of 113 (90.5%) soldiers were able to return to military duty in group A (combined ACLR with modified LET), whereas 51 of 81 (62.9%) of the soldiers who underwent ACLR alone (group B) returned to military duty (P = 0.05). Conclusion: At 24 months postoperatively, combined ACLR plus LET showed a significantly higher RTS rate than ACLR alone. The combined ACLR with the modified LET group also showed a lower failure rate than the ACLR alone group. No marked differences were observed in KOOS sub-scores, IKDCsubjective, and Tegner activity scores.

Preservation of the MMPH and Status of the Notch Configurations Are Important Factors for Successful Revision ACL Reconstruction.

The aim of this study was to identify the differences in anatomical factors between the patients who underwent revision and primary anterior cruciate ligament reconstructions (ACLR) and compare the outcomes between the 2 surgeries. Retrospective cohort study. Single institution tertiary academic center between 2014 and 2020. A total of 84 matched patients who underwent revision (group I) or primary ACLR (group II). Radiological evaluations were performed using side-to-side differences (SS-D), femorotibial angle, and posterior tibial slope. The medial meniscus posterior horn status as width (MMPHW), medial tibial plateau width (MTPW), notch configurations, tunnel positions, and sagittal graft angle were measured using 3D-CT and magnetic resonance imaging (MRI). Graft signals were assessed using MRI. The clinical outcomes were assessed. Group I showed larger SS-D and higher mean Howell grade of anterior cruciate ligament (ACL) graft than group II (P = 0.002 and P = 0.004, respectively). Multivariate regression analyses showed that the decreased MMPHW/MTPW ratio (P = 0.010) and notch width index (P < 0.007) were significantly independent factors associated with the higher Howell grade of ACL grafts. The decreased MMPHW/MTPW ratio (P < 0.001) was a significantly independent factor associated with larger SS-D. In the subgroup analysis, all patients in the notchplasty group showed wider notches postoperatively (P < 0.001). Revision ACLRs resulted in worse ACL signal intensity and stability outcome. The results of this study suggest that it may be important to preserve the MMPHW as much as possible and check notch configurations, especially during a revision ACLR.

Superior Biological Healing of Hamstring Autografts Compared with Tibialis Allografts after Anterior Cruciate Ligament Reconstruction: A Propensity Score Matching Analysis Based on Second-Look Arthroscopy.

Background and Objectives: Remodeling and healing of the graft are crucial processes for long-term graft survival after anterior cruciate ligament reconstruction (ACLR). However, few studies have objectively evaluated the differences in graft healing between autografts and allografts. This study aimed to compare the status of the anterior cruciate ligament (ACL) grafts between hamstring tendon (HT) autografts and tibialis anterior tendon (TAT) allografts using second-look arthroscopy. Materials and Methods: The outcomes of 193 consecutive patients (153 males and 40 females, with an average age of 30.38 and BMI of 25.43 kg/m2) who underwent second-look arthroscopy following primary ACLR were retrospectively reviewed. Prior to participating in this study, all patients provided written informed consent. The patients were divided into two groups: those with HT autografts and those with TAT allografts. Confounding factors were matched between the two groups using propensity score matching (PSM). ACL graft status was assessed during second-look arthroscopy using a numeric scale system based on the degree of four parameters: graft tension, continuity, synovium coverage, and vascular marking. Clinical outcomes were assessed using the Lysholm and International Knee Documentation Committee (IKDC) scores. Graft status and clinical outcomes were compared between the two groups. Additionally, a subgroup analysis based on the timing of the second-look arthroscopy (12-24 months vs. >24 months after the initial ACLR) was conducted. Results: After PSM, 62 patients were included in each group. The second-look arthroscopy was conducted at 23.6 ± 6.6 months for the HT group and at 24.0 ± 7.9 months for the TAT group (p = 0.749). The continuity and tension of the ACL graft were not significantly different between the two groups (p = 0.146 and 0.075, respectively). However, the TAT group exhibited significantly inferior synovial coverage and vascular marking of the ACL graft compared with the HT group (p = 0.021 and 0.007, respectively). These findings were consistent regardless of the timing of the second-look arthroscopy. Clinical outcomes, according to the Lysholm and IKDC scores, significantly improved in both groups with no significant differences (p = 0.386 and 0.733, respectively). Conclusions: Although there were no differences in graft tension and continuity between HT autografts and TAT allografts, the biological healing of ACL grafts, in terms of synovialization and vascularization, was superior in HT autografts compared to TAT allografts.

Anterior Slope-Modifying Osteotomies Alter the Length Change Behavior of the Superficial Medial Collateral Ligament: A Biomechanical Study.

Increased tibial slope has been shown to lead to higher rates of anterior cruciate ligament graft failure. A slope-decreasing osteotomy can reduce in situ anterior cruciate ligament force and may mitigate this risk. However, how this procedure may affect the length change behavior of the medial ligamentous structures is unknown. The purpose of this study was to examine the effect of anterior slope-modifying osteotomies on the medial ligamentous structures. It was hypothesized that (1) decreasing the tibial slope would lead to shortening of the superficial medial collateral ligament (sMCL), (2) while the fibers of the posterior oblique ligament (POL) would be unaffected. Descriptive laboratory study. Eight fresh-frozen cadaveric knee specimens underwent anatomic dissection to precisely identify the medial ligamentous structures. The knees were mounted in a custom-made kinematics rig with the quadriceps muscle and iliotibial tract loaded. An anterior slope-modifying osteotomy was performed and fixed using an external fixator, which allowed modification of the wedge height between -15 and +10 mm in 5-mm increments. Threads were mounted between pins positioned at the anterior, middle, and posterior parts of the tibial and femoral attachments of the sMCL and POL. For different tibial slope modifications, length changes between the tibiofemoral pin combinations were recorded using a rotary encoder as the knee was flexed between 0° and 120°. All sMCL fiber regions shortened with slope reduction (P < .001) and lengthened with slope increase (P < .001), with the anterior sMCL fibers more affected than the posterior sMCL fibers. A 15-mm anterior closing-wedge high tibial osteotomy (ACWHTO) resulted in a 6.9% ± 3.0% decrease in the length of the anterior sMCL fibers compared with a 3.6% ± 2.3% decrease for the posterior sMCL fibers. A 10-mm anterior opening-wedge high tibial osteotomy (AOWHTO) increased anterior sMCL fiber length by 5.9% ± 2.3% and posterior sMCL fiber length by 1.6% ± 1.0%. The POL fibers were not significantly affected by a slope-modifying osteotomy. Tibial slope-modifying osteotomies changed the length change pattern of the sMCL such that an AOWHTO increased whereas an ACWHTO decreased the sMCL strain. This effect was most pronounced for the anterior fibers of the sMCL. The length change pattern of the POL remained unaffected by slope-modifying osteotomy. Surgeons should be aware that anterior tibial slope-modifying osteotomies affect the biomechanics of the sMCL. After an extensive ACWHTO, patients may develop a medial or anteromedial instability, while an AOWHTO may overconstrain the medial compartment.

Posterior Lateral Meniscal Root Repair Through Lateral Tunnel and Anterior Cruciate Ligament Revision: How to Avoid Tunnel Overlapping

Posterior lateral meniscal root (PLMR) tears are commonly observed in conjunction with anterior cruciate ligament (ACL) injuries. The presence of PLMR tears exacerbates knee instability, increasing stress on ACL grafts and accelerating joint degeneration if left untreated. Anatomical repair of PLMR tears is therefore crucial for restoring native knee kinematics and reducing tibiofemoral contact pressures, thereby safeguarding the ACL graft. However, the standard use of a single medial tunnel approach for concomitant PLMR and revision ACL reconstruction may require reconsideration to prevent the potential risks of tunnel overlapping, which could undermine graft anatomical integrity. This article, to prevent the risk of tunnel overlapping, introduces a surgical approach that employs an additional lateral tibial tunnel for PLMR repair, instead of the typically used single medial one, for PLMR repair during simultaneous revision ACL reconstruction.

Late (≥60 years old) and middle adulthood (40-59 years old) patients achieve similar improvement in patient-reported outcomes following ACL reconstruction.

This study aimed to compare the range of motion (ROM), surgical outcomes, and patient-reported outcome measures (PROMs) following anterior cruciate ligament (ACL) reconstruction outcomes in patients 60 years or older at the time of surgery to 40- to 59-year-old patients. In this retrospective cohort study from 2015 to 2022, a 3:1 propensity match was performed to match late adulthood patients (≥60 years old) undergoing ACL reconstruction with middle adulthood (40-59 years old) ACL reconstruction patients. Patients were matched based on sex, ACL graft utilized and concomitant procedures performed during ACL reconstruction. Statistical analysis compared demographics, preoperative injury management, surgical outcomes, PROMs, and minimal clinical important difference (MCID) and substantial clinical benefit (SCB) achievement rates for all ACL reconstruction patients included. Twenty late adulthood and 60 middle adulthood patients who underwent ACL reconstruction were included in the final cohort. Patients who were 60 years or older experienced no difference in reoperation rate (n.s.), incidence of retears (n.s.) or ROM (n.s.) at 1 year post-operatively. There were also no differences in International Knee Documentation Committee (ΔIKDC) (31.3 ± 19.1 vs. 34.2 ± 18.2, n.s.) or ΔPCS-12 (12.4 ± 9.8 vs. 12.9 ± 10.8, n.s.) scores at 1 year post-operatively. Furthermore, the younger and older patient cohorts demonstrated similar rates of achieving the MCID (80.0% vs. 83.3%, n.s.) and SCB (50.0% vs. 61.7%, n.s.) scores for IKDC. Patients 60 years or older and 40- to 59-year-old patients demonstrated similar outcomes after undergoing ACL reconstruction with allograft. This study concludes that ACL reconstruction in late adulthood can still be a successful treatment option and should allow surgeons to feel more comfortable when performing indicated surgical intervention for older patients who experience an ACL tear. Level III, Therapeutic III, retrospective cohort study.

Primary Anterior Cruciate Ligament Injury: Extrinsic and Intrinsic Risk Factors.

Anterior cruciate ligament (ACL) injuries continue to increase in incidence despite extensive research into prevention strategies. Many extrinsic and intrinsic risk factors for sustaining ACL injuries have been identified and continue to be investigated. Extrinsic risk factors for ACL injury relate to the athlete's environment, such as the shoe-surface interaction, weather conditions, and sport played. Intrinsic risk factors relate to the athlete's sex, hormones, knee anatomy, landing and pivoting biomechanics, and neuromuscular control. Recent research has highlighted the role of the bony morphology of the proximal tibia and distal femur on primary ACL injury risk, as well as the risk for ACL graft failure. Sex differences in bony and ligamentous morphology of the knee, neuromuscular control, and hormonal factors, such as serum relaxin levels and variations within the menstrual cycle, have been correlated with a higher risk of noncontact primary ACL injuries in female athletes compared with male athletes.

Five-year Outcomes Following Anterior Cruciate Ligament Reconstruction: Does Sex Impact Patient-Reported Outcomes and Re-operation Rates?

BACKGROUND: Females have been shown to have a two to eight times higher risk of Anterior Cruciate Ligament (ACL) injury than their male counterparts. Despite the clear difference in risk, sex-based differences in outcomes following ACL reconstruction are less well understood. The purpose of this study was to compare 5-year outcomes between males and females who were under the age of 26 at the time of enrollment in an ACL registry. We hypothesize that male and female patients will have similar patient-reported outcome scores, but females will have a higher incidence of ACL graft re-injury. METHODS: Patients undergoing ACL reconstruction while under the age of 26 were included if they also had completed five-year follow-up questionnaires. Outcomes were compared between males and females, and the outcomes of interest included the International Knee Documentation Committee (IKDC), Knee Injury and Osteoarthritis Score (KOOS), ACL Return to Sport after Injury (ACL-RSI), and reoperation. RESULTS: Of the 159 patients enrolled in the registry, 35 had complete follow-up (22%). The average difference between postoperative and preoperative IKDC scores for males and females was 37.9 ± 21.6 and 33.2 ± 26.6, respectively (p=.600). The average difference between postoperative and preoperative KOOS scores for males and females was 31.6 ± 15.4 and 29.2 ± 23.0, respectively (p=0.731). The average ACL-RSI for males and females was 79.8 ± 47.0 and 56.5 ± 31.1, respectively (p=0.088). The incidence of reoperation and ACL re-tear for the entire cohort was 28.6% and 5.7%, respectively. CONCLUSION: Overall, males and females under the age of 26 who underwent ACLR had similar 5-year outcomes regarding outcomes scores after surgical intervention. The ACL-RSI was lower in women, however, failed to reach significance. The reoperation rate for males and females was not statistically significant. ACL reconstruction is a successful operation in young males and females with improvement in knee outcome scores and ability to return to sport.

Anterior cruciate ligament reconstruction: Effect of graft tunnel position on early to mid-term clinical outcomes.

Patient reported outcome measures (PROMs) can be used to assess knee function following anterior cruciate ligament (ACL) reconstruction. Intra-operatively, femoral and tibial tunnels are created to accommodate the new ACL graft. It is postulated that there is an optimum position and orientation of these tunnels and that outcomes from this procedure are affected by their position. To evaluate the influence of graft tunnel position on early to mid-term clinical outcomes following ACL reconstruction. Six PROMs were collected following ACL reconstruction which included the Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee, Lysholm, Tegner, EuroQol-5 Dimension-5 level, and Short Form 12-item Health Survey. A total of 8 radiological parameters were measured from post-operative X-rays relating to graft tunnel positions. This data was analysed to assess for any correlations between graft tunnel position and post-operative PROMs. A total of 87 patients were included in the study with a mean post-operative follow-up of 2.3 years (range 1 to 7 years). Posterior position of tibial tunnel was associated with improved KOOS quality of life (rho = 0.43, P = 0.002) and EQ-5D VAS (rho = 0.36, P = 0.010). Anterior position of EndoButton femoral tunnel was associated with an improved EQ-5D index (rho = -0.38, P = 0.028). There were no other significant correlations between any of the other radiological parameters and PROM scores. Overall, graft tunnel position had very little correlation with clinical outcomes following ACL reconstruction. A few (posterior) tibial tunnel and (anterior) EndoButton femoral tunnel measurements were associated with better PROMs.

Single-bundle ACL combined with ALL reconstruction yields comparable outcomes in patients with varied anatomical risk factors for ACL graft failure

BackgroundAnterior cruciate ligament (ACL) graft failure is influenced by factors such as meniscal tears and tibial plateau slope. Combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction has reduced failure rates; however, its efficacy in high-risk patients remains unclear. This study hypothesized that combined ACL and ALL reconstruction would yield similar clinical outcomes in patients with varying risks of ACL failure.Patients and methodsA total of 76 patients who underwent primary single-bundle ACL reconstruction combined with ALL reconstruction between June 2018 and June 2021 were included. The medial tibial slope (MTS), lateral tibial slope (LTS), and anterior tibial translation (ATT) were measured using magnetic resonance imaging and plain radiography of the knee joint. The meniscal lesions were assessed during surgery. Preoperative clinical assessments and final follow-up were conducted using patient-reported outcome measurements (PROMs), including the International Knee Documentation Committee (IKDC) evaluation, Lysholm knee scoring scale, and Tegner Activity scale. PROMs were collected at least two years postoperatively.ResultsThe average follow-up was 32.5 ± 7.4 months. There were no significant differences in postoperative IKDC score, Lysholm score, or Tegner activity score between patients with or without medial meniscus injury (p = 0.155, 0.914, and 0.042, respectively), with or without lateral meniscus injury (p = 0.737, 0.569, and 0.942, respectively), medial tibial slope > 12° or ≤ 12° (p = 0.290, 0.496, and 0.988, respectively), or lateral tibial slope > 7.4° or ≤ 7.4° (p = 0.213, 0.625, and 0.922, respectively). No significant correlations were found between anterior tibial translation and postoperative IKDC (R = -0.058, p = 0.365), Lysholm (R = -0.017, p = 0.459), or Tegner activity scores (R = -0.147, p = 0.189).ConclusionOur study demonstrates that single-bundle ACL reconstruction combined with ALL reconstruction provides reliable and comparable clinical outcomes in patients with high-risk factors for ACL graft failure, such as increased tibial slope or meniscal injury. Our results suggest that the indications for ALL reconstruction may be expanded to include patients with a high tibial slope or meniscal injury, because these factors have been shown to contribute to increased rotational instability and high rates of ACL graft failure. Future prospective randomized controlled trials with large patient cohorts and long follow-up periods are needed to validate these findings and establish clear guidelines for patient selection and surgical decision-making.Level of evidenceLevel 3.

Outcomes of ACL Reconstruction Utilizing Supercritical CO2-Sterilized Allografts.

Allograft tendons are perceived to have a high ACL graft failure rate in primary anterior cruciate ligament (ACL) reconstruction (ACLR). Historical series may be biased by graft processing methods that degrade the biomechanical properties of donor tendons such as irradiation. Supercritical carbon dioxide (SCCO2) is a validated method of terminally sterilizing biomaterials at physiological temperatures without irradiation, but in vivo use of SCCO2-processed tendon allografts for primary ACLR has not been reported to date. ACLR with SCCO2 allografts would result in acceptable failure rates, subjective knee scores, and clinical evaluation at 2 years postoperatively. Case series; Level of evidence, 4. Patients underwent primary ACLR with terminally sterilized SCCO2-processed human gracilis, peroneus longus, semitendinosus, tibialis anterior, and tibialis posterior tendon allografts. Patient demographics were collected, along with tendon donor age and sex. At 1 year postoperatively, subjective International Knee Documentation Committee (IKDC) and ACL-Return to Sport After Injury (ACL-RSI) scores were collected, as well as clinical evaluation. At 2 years postoperatively, the IKDC and ACL-RSI scores were repeated, and return to sports and further knee injuries were recorded. A total of 144 patients with a medianage of 26 (IQR 14) years formed the study group. Patients were predominately male (58%). The loss to follow-up rate was 8% (n = 12). The mean age of allograft tendon donors was 37 (range 17-58) years, and the majority were male (83%). The mean allograft diameter was 8.9 ± 1.0 mm. At 2 years, ACL graft failureoccurred in 5% (n = 7). All graft failureswere in patients aged ≤25 years (P = .007). Neither donor age (≤40 or >40 years) nor donor sex was associated with graft failure (P > .05). The median IKDC subjective score was 95 and ACL-RSI score was 75. There were no revisions for sepsis within the first 2 years postoperatively. SCCO2 processing of allograft tendons demonstrated satisfactory clinical and patient-reported outcomes at 24 months postoperatively in a consecutive series of patients with primary ACLR, with similar ACL graft failure rates and subjective knee scores compared with those reported in published series of hamstring tendon autograft and fresh frozen nonirradiated allograft.

Patient Perception of Allograft Versus Autograft in ACL Reconstruction Using a Validated Online Survey Marketplace.

Little is known regarding the opinions of the general population on anterior cruciate ligament (ACL) graft options. To evaluate the general population's perception of the use of allografts versus autografts in ACL reconstruction using a previously validated online marketplace platform. A prospective 34-question survey was distributed via the online marketplace. After collecting baseline demographics, participant preferences for ACL reconstruction with an allograft or autograft were established. All respondents completed a preeducation survey, reviewed an evidence-based education sheet, and completed a posteducation survey to assess their understanding. Upon completion, participants were asked which graft they would prefer. Participants were then asked if they would be willing to change their preference based on surgeon recommendation. Finally, participants were asked to rank the factors from the education sheet that were most influential. Cross-sectional study. There were 491 participants that completed the survey (mean age, 39.9 years [range, 19-72 years]; 244 male, 241 female, and 6 nonbinary/third-gender participants). Before reading the education sheet, 276 (56%) reported no graft preferences, 146 (30%) preferred autograft, and 69 (14%) preferred allograft. After reading the provided sheet, 226 (46%) participants preferred autograft, 185 (38%) preferred allograft, and 80 (16%) had no preference. The mean score on the preeducation test was 45%, and the mean score on the posteducation test was significantly greater (61%; P < .01). Overall, 345 participants (83.9%) stated they would change their preference for autograft or allograft if their surgeon recommended it. Surgeon preference (n = 330; 67%), educational information provided (n = 117; 24%), and previous knowledge (n = 44; 9%) were the most important factors for making graft selections. The mean ages of the participants selecting each graft type before and after education were as follows: allograft (37.8 ± 10.1 vs 40.6 ± 11.8 years; P = .05), autograft (38 ± 11.5 vs 39.5 ± 10.1 years; P = .21), and no preference (41.5 ± 11.2 vs 39.4 ± 11.8 years; P = .16). Education resulted in a greater number of individuals' reporting a preference in graft type (either allograft or autograft) compared with preinformation questioning. In addition, 83.9% of the participants were willing to switch their graft choice if recommended by their surgeon.

All-Inside Anterior Cruciate Ligament Reconstruction Using Full-Thickness All-Soft-Tissue Quadriceps Tendon Autograft With Independent Suture Tape Augmentation

The anterior cruciate ligament (ACL) is the most frequently injured knee ligament that requires surgical intervention. Surgical options to address ACL ruptures include reconstruction using autograft or allograft or performing primary repair. Subsequent ACL graft failure is a significant postoperative concern in the younger patient population. The addition of suture tape to the final construct is thought to protect the graft during moments of high stress by increasing graft stiffness under high load and preventing substantial graft elongation. Given the normal anatomic lengthening of the ACL from knee flexion to full extension, final fixation of both the suture tape and the graft is done with the knee hyperextended to avoid overconstraint. The use of adjustable loop fixation for both femoral and tibial fixation with the all-inside technique allows the graft to be retensioned after final suture tape fixation and subsequent knee cycling. This ensures that the suture tape is slightly laxer than the graft so that the graft experiences loads that are essential for its healing, with the suture tape sharing the load only during times of high stress.

Patient Preferences for Graft Selection in Anterior Cruciate Ligament Reconstruction.

Selecting an appropriate graft for anterior cruciate ligament (ACL) reconstruction requires consideration of a patient's preferences, goals, age, and physical demands alongside the risks and benefits of each graft choice. To determine the most popular ACL reconstruction grafts among patients and the most important factors influencing their decisions. Cross-sectional study; Level of evidence, 3. Patients undergoing ACL reconstruction between October 2022 and April 2023 completed a survey either before (nonconsult group) or after (consult group) speaking with their surgeon, who provided an evidence-based description of the pros and cons of an allograft and the following autografts: bone-patellar tendon-bone (BPTB), hamstring tendon (HT), and quadriceps tendon (QT). Patient characteristics, graft choice, information influencing their graft choice, and surgeon recommendation were collected and compared between the groups. Among the 100 included patients, 59.0% were male, and the mean age was 28.3 ± 10.4 years. The most popular grafts were the BPTB (56.0%), followed by the QT (29.0%), HT (8.0%), and allograft (7.0%). No significant difference was observed in the graft selection between the consult group (n = 60; BPTB, 46.7%; QT, 38.3%; HT, 8.3%; allograft, 6.7%) and nonconsult group (n = 40; BPTB, 70.0%; QT, 15.0%; HT, 7.5%; allograft, 7.5%) (P = .0757). In the consult group, 81.7% of patients selected the graft recommended to them by their surgeon. The top 2 graft selection reasons were usage in professional athletes and failure rates, while the top 2 ACL surgery concerns were returning to their desired level of athletics and graft failure risk. Among the 93 patients who researched their ACL graft options before their visit, the most popular information source was some form of media (72.0% [67/93]). The study findings underscore the importance of patient preference and surgeon recommendation in a patient's graft selection and highlight the need to be cognizant of the information sources available to patients when researching their graft options.

Poster 354: Tibiofemoral Bone Shape Features Are Associated with Re-Tear after Anterior Cruciate Ligament Reconstruction

Introduction: Knee bony morphology is linked to anterior cruciate ligament (ACL) injury, ACL graft failure, and osteoarthritis (OA) risk, and employing tools such as statistical shape modeling could identify individuals prone to these joint conditions. Re-tear after ACL reconstruction remains a common and devastating complication, and therefore, recognizing patients at high risk of graft failure before primary ACL reconstruction is crucial for potential intervention to reduce failure rates. Magnetic resonance imaging (MRI) is most commonly obtained in the setting of possible ACL injury and before ACL reconstruction surgery, yet currently available MRI-based bone shape assessment methods require high-resolution sequences or manual segmentation, limiting feasibility of large-scale analysis. The development of automated tools for bone shape extraction from clinical MRI could allow for three-dimensional statistical shape modeling across large datasets. We established an automated pipeline for bone segmentation from proton density (PD)-weighted MRI scans, aiming to extract knee bony morphology from preoperative clinical MRIs in patients with ACL injuries. We hypothesized that our segmentation pipeline could uncover specific tibiofemoral joint bone shape features associated with ACL re-tear after reconstruction. Objective: To identify bone shape features prior to initial primary ACL reconstruction in patients with eventual ACL graft re-tear compared to those with a known, intact ACL graft. Methods: Patients who retrospectively experienced a subsequent re-tear after reconstruction within three years of initial injury were compared to those without a re-tear within three years (20 without subsequent re-tear, 22 with subsequent re-tear for distal femur; 22 without subsequent re-tear, 19 with subsequent re-tear for proximal tibia). The control group had MRI scans at 3 years after reconstruction that confirmed an intact ACL graft. An automatic femur and tibia segmentation framework was developed by training two deep convolutional neural networks using clinical, two-dimensional PD-weighted knee MRI sequences (3.5 mm slice thickness) from patients with ACL tears. Using the segmentation pipeline, bone was automatically segmented from preoperative clinical PD-weighted knee MRI sequence (3 mm slice thickness), three-dimensional triangulated meshes were generated, scaled to a reference, and aligned and matched to an atlas using Iterative Closest Point algorithm. Modes of shape variance were extracted from principal component analysis (PCA). The effect of each mode is modeled by three-dimensional surfaces for each specific shape feature. Modes were considered statistically significant if the mean principal component score between groups was p&lt;0.05 using Students T-test. Results: Statistical shape modeling of the femoral condyles using 15 PCA modes reveals significant differences (p &lt; 0.05) in Modes 1 and 4 at the initial injury in patients who subsequently experienced ACL re-tear after reconstruction compared to those without re-tear. Femur Mode 1 is characterized by a narrower intercondylar notch width, a wider medial condylar width, and an increased ratio of femoral condylar offset in patients with ACL re-tear. Femur Mode 4 illustrates a more prominent trochlear sulcus and increased surface area along the lateral femoral condyle relative to the medial condyle in patients with ACL re-tear. The initial 15 PCA modes of the distal femur collectively account for 75.04% of the normalized accumulated total variance. Statistical shape modeling of the tibial plateau with 15 PCA modes reveals that Mode 7 is significantly different (p &lt; 0.05) at the initial injury in patients who experienced subsequent ACL re-tear after reconstruction compared to those without re-tear. Tibia Mode 7 indicates diminished ACL facet prominence, a squared lateral tibial plateau, and a broader, flatter tibial spine in patients with subsequent ACL re-tear. The first 15 PCA modes of the proximal tibia collectively explain 73.60% of the normalized accumulated total variance. Conclusions: Using an automatic bone segmentation pipeline on preoperative clinical MRIs, we identify specific shape features in the tibiofemoral joint associated with ACL re-tear after reconstruction. Patients with subsequent ACL re-tear exhibit a variety of distinct three-dimensional morphology differences, including reduced intercondylar notch width, wider medial condylar width, increased lateral tibial plateau convexity, and broader, lateralized tibial spine, uncovered using statistical shape modeling. Statistical shape modeling identifies three-dimensional morphology patterns, thus capturing differences otherwise unaccounted for by traditional two-dimensional measurements. This approach offers predictive potential for patients at risk of ACL re-tear, improving treatment decisions for those with high-risk morphologic features.

Poster 349: Tobramycin-Soaked Grafts for the Prevention of Infection Following Anterior Cruciate Ligament Reconstruction: A Retrospective Review of Infection Rate

Objectives: Infection can be a devastating complication of anterior cruciate ligament (ACL) reconstruction. Soaking or wrapping grafts in vancomycin solution has been adopted by many surgeons to prevent infection following ACL reconstruction. Recent meta-analysis demonstrated a significant reduction in the incidence of deep infection in vancomycin-soaked grafts to be 0.09% compared to 0.74% for nontreated grafts.1 Tobramycin may provide an alternative for patients with vancomycin allergies or if vancomycin is not available. The purpose of this study is to evaluate the incidence of deep and superficial infection following ACL reconstruction in young patients with tobramycin-soaked grafts as well as characterize potential risk factors for infection. We hypothesize that tobramycin-soaked grafts result in a low deep infection rate, comparable to that of vancomycin-soaked grafts published in the literature. Methods: A total of 812 consecutive patients under age 20 who underwent ACL reconstruction at an academic medical center between 2010 and 2020 with tobramycin-soaked grafts were identified. Retrospective chart review was performed to identify postsurgical superficial and deep wound infections, as well as other pertinent surgical characteristics. The incidence of infection in this tobramycin wrap cohort was compared to the incidence of infection of vancomycin wraps as published in the literature. Results: Superficial wound infections occurred in 24 patients (2.96%) and 0 deep joint infections were identified in the tobramycin wrap cohort. The incidence of infection was 3.16% in 728 patients who received prophylactic perioperative intravenous Cefazolin and 1.23% infection incidence in 81 patients who received prophylactic perioperative Clindamycin (p = 0.30). In addition, no significant difference in incidence of superficial infection was found with patient age, sex, body mass index, or graft type. Conclusions: Tobramycin-soaked ACL grafts demonstrate a low infection risk comparable to that of vancomycin-soaked ACL grafts. The type of prophylactic IV antibiotic used in this young cohort did not impact the incidence of superficial wound infection. Further work with larger and older cohorts is needed to better characterize risk factors for postoperative infection following ACL reconstruction for all ages and comorbidities.

Paper 01: Clinical Outcomes Following ACL Reconstruction with Slope Reducing High-Tibial Osteotomy: A Matched Case-Control Study

Objectives: Despite recent efforts, the reinjury rate following anterior cruciate ligament (ACL) reconstruction remains high, with documented reports of up to 30%. According to retrospective evidence, high posterior tibial slope (≥12°) has been identified as an anatomic risk factor contributing increased graft reinjury rates. Surgeons are therefore exploring the effectiveness of slope reducing high tibial osteotomy (SRO) as a means of modifying this potential risk factor. While cadaveric models suggest that this surgical procedure decreases the forces across the ACL graft, there are few clinical trials examining its’ safety and clinical effectiveness in patient samples. Therefore, the purpose of this study is to compare functional performance and graft reinjury rates between patients undergoing ACL reconstruction surgery with SRO versus matched controls undergoing isolated ACL reconstruction. We hypothesized that patients undergoing ACL reconstruction with SRO would exhibit similar performance outcomes with a low failure rate when compared to their matched counterparts. Methods: A retrospective matched-case control study was conducted in accordance with the ‘Strengthening the Reporting of Observational Studies in Epidemiology’ guidelines for patients undergoing ACL reconstruction (Figure 1), utilizing a single surgeon database (n=1978). The experimental group (ACL+SRO) consisted of patients ages 18-50 years old that were at least 24-months out of ACL reconstruction with a concomitant SRO. Patients were age, sex, and revision-matched to a cohort of individuals undergoing isolated ACL reconstruction. Exclusion criteria consisted of contralateral knee injury (&lt;24 months prior to surgery), isolated coronal-plane high tibial osteotomy, and multiligamentous knee injury. Patient demographics and surgical data were obtained, including pre/postoperative posterior tibial slope (o) for the ACL+SRO group and presurgery activity levels. Data were gathered at return to sports and included knee range of motion, single-leg balance, single-leg hop testing, and self-reported International Knee Documentation Committee and ACL-Return to Sports After Injury (ACL-RSI) scores. Complications and injury surveillance was conducted throughout the postoperative follow-up period. Primary outcome measures included the Single Assessment Numeric Scale (SANE), and graft failure rates at two-years. Secondary outcomes included return to sport rate and level of participation, and postoperative complications (infection, loss of motion, deep vein thrombosis, etc). Generalized Linear Models and chi-square analyses were conducted using SPSS (IBM, Chicago IL) to compare groups with an a-priori alpha level of .05. Results: Of the 1978 patients in the ACL registry, 48 met the study criteria and were included in the analyses (ACL+SRO group, n=24; Isolated ACL group, n=24). Baseline comparisons revealed that the ACL+SRO group had a higher bodyweight (200.9 ±35.1 vs 179.7 ±33.9, P &lt;.001) and subsequent higher body mass index (29.7 ±4.6 vs 26.7 ±5.0, P = .044), Table 1. Additional baseline differences included ACL graft type, and staged procedures ( P &lt; .05, Table 2). The mean preoperative posterior tibial slope was 17.0° ±2.7° and 7.0° ±2.2° following SRO (mean diff: -10.0°, P &lt;.001). Table 3 depicts the comparisons at return to sport, with the ACL+SRO group demonstrating longer time to return ( P &lt; .001) and lower ACL-RSI scores ( P = .027). At 2 years, there were no statistical differences in SANE score (85.3 ±7.3 vs 88.2 ±9.7, P = .349), graft reinjury rate (0.0% vs 0.0%, P = 1.000), rate of return to sports (85.7% vs 91.7%, P = .844), or level of return to sports between groups with 45.8% (n=11) of the ACL+SRO group returning to a level I or II cutting and pivoting sport versus 54.2% (n=13) in the Isolated ACL group ( P = .656). There were no reported postoperative infections or deep vein thromboses in either group (P &gt; .05). Conclusions: The current study suggests that SRO in the setting of ACL reconstruction for large posterior tibial slope deformities is effective at correcting malalignment, restoring objective and self-reported function, and avoiding graft failure out to 2 years. This procedure also holds promise to allow a majority of patients to return to various levels of sporting activities. To our knowledge, this is the first comparative study examining the return to sports and 2-year outcomes of this population to a matched isolated ACL cohort. While these data do provide evidence for ongoing investigation, we recommend the performance of larger clinical trials to confirm these results. [Figure: see text][Figure: see text][Figure: see text][Figure: see text]

Poster 387: Application of Survival Machine Learning Methodology to Predict Time-Dependent Risk of Revision ACLR Graft Failure in the MARS Cohort

Objectives: Previous machine learning (ML) analysis has shown that a novel ML model built using the Multicenter Anterior Cruciate Ligament (ACL) Revision Study (MARS) cohort data can predict graft failure at 6 years postoperatively as a binary outcome with moderate ability. However, binary classification does not consider the time-to-event component of graft failure as an outcome. In contrast, survival models can factor the time-to-event component of an outcome, incorporate time-dependent variables, and appropriately process censored data to deliver more clinically meaningful outcome predictions. While the previous binary classifier can provide information about whether the primary outcome graft failure will occur at 6 years, survival analysis models are able to provide information on when graft failure occurs (for example, within 2, 4, or 6 years). Therefore, this study sought to apply ML survival analysis methodology to the MARS cohort data to produce a model that can most accurately estimate the probability of revision ACL reconstruction (rACLR) graft failure within 2, 4, and 6 years postoperatively, and identify factors that impact probability estimates at each of these time horizons. Methods: rACLR patients were prospectively recruited by the MARS group. Preoperative radiographs, surgeon-reported intraoperative findings, and 2 and 6-year follow-up data on patient-reported outcomes (PROs), subsequent knee surgeries, and graft failure were obtained. ML models including Cox Proportional Hazards (CoxPH), XGBoost Survival Embeddings (XGBoost), Random Survival Forest (RSF), Extra Survival Tree (EST), and CoxBoost, were built to predict the probability of graft failure within 2, 4, and 6 years postoperatively. Validated performance metrics and feature importance measures were used to evaluate model performance. Results: The cohort included 1142 patients, of which 4.8% (n = 55) experienced documented graft failure during the 6-year postoperative period. CoxBoost demonstrated the highest discriminative power across all studied time points (Timepoint: Time Dependent C-index | 2-year: 0.725 ± 0.127 | 4-year: 0.669 ± 0.057 | 6-year: 0.645 ± 0.054), with well-calibrated scores (Timepoint: Time dependent Brier Score | 2-year: 0.023 ± 0.012 | 4-year: 0.035 ± 0.010 | 6-year: 0.046 ± 0.012) as listed in Table 1 and Table 2 respectively. Based on the Kaplan Meier survival plot, the survival probability (probability of not tearing the ACL graft) at 2, 4, 6 years was 0.977, 0.965, and 0.954 respectively. Within the context of the predictive models, features deemed important for CoxBoost differed from those deemed important for CoxPH predictive ability. Conclusions: Survival machine learning models can predict the risk of rACLR graft failure up to 6 years postoperatively, with the most robust predictions at the 2-year postoperative timepoint. While external validation with further combined registry datasets is required, this present study builds on prior ML analyses towards the development of a bedside calculator for rACLR outcome prediction and risk stratification.

Poster 356: Patient Perception of Autograft Options in ACL Reconstruction Using a Validated Online Survey Marketplace

Objectives: Anterior cruciate ligament (ACL) reconstruction is the gold standard treatment for ACL tears. ACL graft reconstruction is commonly performed with an autograft. Common autograft modalities include bone-patellar tendon-bone (BPTB), quadriceps tendon (QT), and hamstring tendon (HT) grafts. This study sought to evaluate the general population’s perception of the use of BPTB, QT, and HT autografts in ACL reconstruction. Methods: A prospective cohort study was performed utilizing a 36-question survey. Participants were paid, and the survey was distributed via a clinically validated, public, online marketplace in June 2023. After collecting baseline demographics, participants were queried on whether they held a preference for autograft type without additional information. All respondents then sequentially completed a pre-education survey to assess baseline knowledge, reviewed information from an evidence-based information sheet (Figure 1), and a post-education survey to assess understanding of the provided material. Upon completion, participants were again asked which treatment modality they would prefer. Additionally, participants were queried on whether they would be willing to change their preference based on surgeon recommendation. Finally, participants were asked to rank the factor that was most influential to their final decision. Results: In total, there were 491 participants that completed the survey. The average age was 39.9 (range, 19-72), there were 244 males, 241 females and 6 that preferred not to respond. 362 (74%) patients reported earning at least a bachelor’s degree and 362 (74%) reported that they did not work in healthcare. Prior to participant education, 19.3% (n=95) preferred BTB, 18.7% (n=92) preferred QT, 12.6% (n=62) preferred HT, and 53.4% (n=262) had no preference. Following education, a significantly greater number of participants chose each graft type; 37.7% (n=185, p&lt;0.01) preferred BTB, 21.6% (n=106, p&lt;0.01) preferred QT, 13.8% (n=68, p&lt;0.01) preferred HT. Significantly fewer participants had no preference 26.9% (n=132, p&lt;0.01). The average score on the pre-information test was 35.0% while the average score on the post-information test was significantly greater, 50.0% (p&lt;0.01). The most important factors in autograft decision making were surgeon preference (n=357, 72.7%), the provided information (n=104, 21.2%), and previous experiences (n=30, 6.1%). In total, 424 (86.4%) participants said they would switch their graft preference if their surgeon recommended it. Conclusions: The primary finding of this study was that surgeon preference is the most influential factor for the general population when surveyed about their graft preferences for ACL reconstruction with autograft. This study showed that 86% of participants were willing to switch their preference if their surgeon recommended switching. Additionally, significantly more patients chose a specific graft type (BTB, QT, HT) after reading an evidence-based information sheet on the graft types. The findings of this study imply that informed patients are capable of participating in medical decision making with respect to their graft choices in ACL reconstruction, and that providing educational information can help surgeons and patients work together to optimize their care. [Figure: see text]